Fuel-fired water heaters are generally formed to include a water storage tank with a burner disposed in a combustion chamber. For example, gas-fired residential and commercial water heaters are generally formed to include a vertical cylindrical water storage tank with a gas burner disposed in a combustion chamber below the tank. In such water heaters, the burner is supplied with a fuel gas through a gas supply line, and combustion air is supplied through one or more air inlet openings providing communication between ambient air and the interior of the combustion chamber.
In order to permit the flow of combustion air into the combustion chamber, while at the same time prevent the outflow of flames from the combustion chamber, various proposals have been made to provide the combustion chamber with an exterior wall portion having a spaced series of flame quenching openings formed therein. Such openings may be configured to permit the ingress of combustion air into the combustion chamber, while at the same time preventing the passage of combustion chamber flames outwardly through these openings. Accordingly, in the event that extraneous flammable vapors enter the combustion chamber with combustion air inwardly traversing these flame quenching openings, flames resulting from ignition of the incoming flammable vapor will be contained within the combustion chamber.
A fuel-fired heating appliance, such as a water heater, having an improved perforated combustion chamber flame arrestor plate is described in detail in U.S. Pat. No. 6,422,178 B1 to Lannes et al., entitled FUEL-FIRED HEATING APPLIANCE WITH LOUVERED COMBUSTION CHAMBER FLAME ARRESTOR PLATE, which is incorporated herein by reference. Such appliances represent an is improvement over prior designs.
However, there remains a need for an improved method of manufacturing a portion of a combustion chamber that can be used in water heaters generally, including those water heaters having flame arrestor plates.